Sash lock



July '29, 1952 J. c. EMERSON SASH LOCK Filed Jan. 17, 1950 John 6. Emwwn INVENTOR.

Patented July 29, 1952 UNITED STATES PATENT OFFICE SASH LOCK John C. Emerson, Hull, Mass. Application January 17, 1950, Serial No. 138,987 4 Claims. (01. 292-241) This invention relates to an improved sas lock of the type wherein a rotatable cam plate mounted on the top rail of the lower sash is engageable with and disengageable from a hook member mounted on the lower rail of the upper sash.

The primary object of the present invention is to provide a sash lock of the abov kind wherein the cam plate is slidably mounted for movement toward and from the hook member and springpressed toward the latter, whereby the cam plate will pass and engage beneath the hook member to automatically lock the sashes closed when the lower sash is lowered with the cam plate rotatably adjusted to the position wherein its cam flange is inoperatively disposed.

Another object is to provide non-positive means to prevent accidental turning of the cam plate when turned to the position wherein its cam flange is inoperatively disposed.

A further object is to provide a lock of the above kind which is simple in construction and efficient in operation.

The exact nature of the present invention will be apparent from the following description when considered with the accompanying drawing, in which:

Figure l is a view showing the present lock in top plan and applied to the sashes of a window, the sashes being locked in closed position.

Figure 2 is a vertical section taken on the line 2-2 of Figure 1.

Figure 3 is a view somewhat similar to Figure 2 with the lower sash unlocked and slightly raised.

Figure 4 is an enlarged fragmentary horizontal section taken on the line 4-4 of Figure 3.

Figure 5 is a view somewhat similar to Figure 4 showing the position of the cam plat pintle when the cam plate is operatively disposed with its cam flange engaged with the hook member.

Referring in detail to the drawing, 5 indicates the conventional hook member secured by screws 6 on the lower rail I of the upper sash and having an overhanging hook 8 adapted to coact with a rotatable cam plate 9 mounted on the upper rail I0 of the lower sash to lock the sashes in closed position. The cam plate 9 has the usual cam flange II at on side which is engageable with the hook 8, when the cam plate is rotated in the direction of the arrow (Figure 1), to draw the rails I and I0 together and prevent them from rattling. An extension I2 is provided on one end of flange I I and forms a handle for use in rotating the cam plate.

In accordance with the illustrated embodiment of the present invention, a hollow base I3 is provided which is secured by screws I4 on the rail I0 and has a top wall I5 provided with an elongated slot I6 that extends transversely of the planes of the sashes. Fixed to the cam plate 9 is 2. depending pintle I! that extends through the slot I6 and is rotatable and laterally slidable therein. The pintle I! also extends through and is rotatable in an opening I8 of a slide or plate I9 slidably disposed within and against the under side of the top wall I5 of base I3. A washer 2.0 is riveted to the lower end of pintle I! in spaced relation to and below the plate I9. The portion of pintle I1 between slide or plate I9 and washer 20 has a flat side 2| adapted to be engaged by a leaf spring 22 to prevent accidental turning of the cam plate 9 when the latter is rotatably adjusted to the position wherein its cam flange H is away from hook 8 and inoperatively disposed, as shown. The side of cam plate 9 opposite the flange I I is flangeless and has a downwardly and inwardly beveled edge 23. A spring 24 acts upon plate I 9 to force the cam plate 9 toward hook member 5 with the pintle I! at the outer end of slot I6 and with the flangeless side of the cam plate in the path of hook 8. The arrangement is such that when the lower sash is lowered to closed position, the cam plate 9 will be cammed inwardly by hook 8 against th action of spring 24, as shown in Figure 3, so as to pass said hook, whereupon spring 26 will force the cam plate outwardly beneath said hook as shown in Figure 2. To release the lower sash, the cam plate is manually slid inwardly to disengage it from beneath the hook 8. By turning the cam plate from the position of Figures 1 and 2, the flange I I will engage hook 8 and draw the rails I and II) together, as usual. Spring 22 may be held at its ends between lugs 25 and 26, while spring 24 may be engaged at its ends over pins 21 and 28, respectively fixed to plat I9 and base I3.

It will be seen that the present device will automatically lock the sashes even if the cam plate is not turned to draw the sashes together. Also, a more durable and efiicient device is had than would be possible by providing a pivoted hook member, as heretofore proposed. Minor changes in construction are contemplated within the spirit of the invention as claimed.

Having described the invention, What is claimed as new is:

1. In a sash look, a base adapted for attachment to the top rail of a lower sash, a cam plate mounted upon said base for rotation about a vertical axis and for limited horizontal sliding movement outwardly into and inwardly out of engagement beneath the hook of a hook member attached to the lower rail of an upper sash, and a spring acting to slide the cam plate outwardly, said cam plate having a beveled edge adapted to coact with the hook for shifting the cam plate inwardly and laterally when the lower sash is lowered to allow the cam plate to pass and engage beneath the hook and automatically lock the sashes in closed position.

2. The construction defined in claim 1, said base being hollow and having a top wall provided with an elongated slot, a pintle fixed tov said cam plate and rotatable and laterally slidable in said slot, and a slide mounted in the base and having said pintle journaled therein, said spring being disposed in said base and acting on said slide.

3. The construction defined in claim 1, said base being hollow and having a top wall provided with an elongated slot, a pintle fixed to said cam plate and rotatable and laterally slidable in said slot, and a slide mounted in the base. and having said pintle journaled therein, said spring being disposed in said base and acting on said slide, a washer secured on the lower end of the pintle, and a leaf spring mounted on the slide and engaging the pintle between the slide and the washer to prevent accidental turning of the cam plate.

4. In a sash lock, a base adapted for attachmentto the top rail of a lower sash, a cam plate mounted upon said base for rotation about a vertical axis and for limited horizontal sliding movement outwardly into and inwardly out of engagement beneath the hook of a hook member attached to the lower rail of an upper sash, and a spring acting to slide the cam plate outwardly, said cam plate having a bevelled edge adapted to coact with the hook for camming the cam plate inwardly when the lower sash is lowered to allow the cam plate to pass and engage beneath the hook and automatically lock the sashes in closed position, said base being hollow and having atop wall provided with an elongated slot, a pintle fixed to said cam plate and rotatable and laterally slidable in said slot, and a slide mounted in the base and having said pintle journaled' therein, said spring being disposed in said base and acting on said slide, a washer secured on the lower end of the pintle, and a leaf spring mounted on the slid and engaging the pintle between the slide"; and the washer to prevent accidental turning of the cam plate.

JOHN C. EMERSON.

REFERENfiES CITED Thefollowing references are of record inthe file of this patent:

UNITED STATES PATENTS Number Name Date 112,717 Judd -1 Mar- 1 1-, 18.71 661,404 Hubbard Nov. 6, 191

1,901,974 Macy Mar. 21,1933 

